Pump jack



Oct. 19 1926.

E. E. STEVENSON PUMP JACK Filed August 18, 1925 4 Sheets-Sheet 1 lflvenfai.

Edward zfS/e'aensazz Oct. 19, 1926.

E. E. STEVENSON PUMP JACK Filed August 18 4 Sheets-Sheet s UJQJLLILL] Ifiuezz/ar. Edward E 57 0025022 n4 War/fey kw mw 4 m m Q m MA R N @w w\ a Q. in

Patented Oct. 19, 1926.

UNI-TED" STATES ()FFICE.

EDWARD E l sr'nvnnsoiv, or Los aneithas, eaemaai assronoa cro n. & B. was

a SUPPLY commas, or LOS Anenmis, cALIFoRNIA, A

Fonnm.

Gendarme on CALI- PUMP JACK.

Application filed'Au gust 18; 1925. Serial No; 50,929.

This invention relatesgenerally to pump jacks or power heads such as are used for reciprocating deep well pumps of the plunger type, and more particularly concerns jacks or heads of the type wherein straight line reciprocatory movement is generated by the use of double cranks in association with planetary gearing.

The many advantages of this type of head over the commonly used walking-beam and pitinan ty ie or the crank, connecting rod and cross. 'ead' type are too well known to warrant discussion here though they may be briefly summarized by pointing out the inherent weaknesses of the lasttwo named types and statinggenerally that the straightline power head has none or" these weaknesses. For example, in order to get the highly desirable long stroke, the angularity ii of the pitnian or connecting rod becomes greatly excessive and practically prohibitive, the size and weight of the supporting structure and driving gear or pulley becomes excessive, excessive friction is set up in. the working parts, and the entire assembly is relatively unstable and prone to wrack and sway when power is applied thereto, consequently reducing the useful life of the mechanism to a relatively short span and greatly so lowering its efliciency during this span.

Yet, in spite of the acknowledged superiority of the straight line or rectilinear movement type of head, the older types of jacks continue in common use, due mainly to the failure to produce an uncomplicated straight line head which may bernanufactiired for a reasonable sum and yet be suffi ciently sturdy and stable to stand the heavy duty to which it is exposed under service conditions. 7

Therefore, it is the general object of the present invention to provide a straight line head which is of an exceedingly simple and eflicient nature and yet capable of being stoutly built without becoming over-massive,

these features being of advantage from the standpoints of manufacturing, space andupkeep economy.

To produce these generalbeneficialresults I have devised a number of novel arrangements but these may be understood better Fig. 5 is an enlarged section on line 5-5 ct Fig. 1;

Fig. 6 isan enlarged section, partly in elevation,- on line 6-6 of Fig. 2, the clamping eyes of the rod grip being omitted;

Fig. 7 is a section on line 77 of Fig. 6;

Fig. 8 is an enlarged section on line 8-8 Fig. 6, butshowing the clamping eyes of the. grip in place; i c

Fig. 9 is a detached view of the grip as viewed from the position of arrow 9 in Fig. 8;

c Fig. 10 is a section on line 10-1O of Fig. 9; and

Fig. 11 is a fragmentary View of Fig. 8, looking in the directionof arrow 11.

First, I will describe the supporting structure of the head with some particularity, but while novelty resides in and is claimed for this structure, it will .be understood that the invention, considered in its broader aspects, is not limited to this particular showing, and

such claims as do not specify the supporting structure" illustrated are not to be construed as limited thereby.

Supporting frame 10 has tripodal characteristics, the rear leg of the tripod being a vertical angle iron .11 so arranged that axis A (Figs. 3 and 4) of the frame bisects the angle between its flanges.

As viewed from the side (Fig. 1) front legs 12, which are channels placed with flanges out, incline upwardly and rearwardly towards the top of leg 11, and, as viewed from the front (Fig. 2), said legs 12 extend upwardly in parallel relation to bend 13 and thence incline inwardly towards each other and to leg 11, being riveted to said rear leg at 14-. L-egs'12 are stiffened by gusset plates 12 and have shoe plates 15 provided with removable rollers 45.

notches 16 to take anchor bolts 17; while shoe plate 18 has angle irons 19 which are riveted to leg 11, angle irons 19 and plate 18 being apertured to take anchor bolts 20. Bolts 20 serve to hold the frame to derrick floor F or any suitable foundation or footings.

The three legs are tied together by cross bars 21 and brace plates 22, said plates being riveted to the legs at 23 and extending horizontally forwardly to the vertical extensions 24 of inverted U-shaped member 25, the lower ends of said member, being riveted to tripod legs 12 at 26. Rivets 27 connect plates 22 and extensions 24, the plates also serving as carrying members for certain parts of the jack mechanism. Riveted at 28 to the forward face of member 25, which may be termed a gear supporting member, is a face plate 29 having a central aperture 30 of a size to permit free rotation of the crank mechanism to be described.

A cap plate 31 is riveted to the tops of the legs 11 and 12 through angle brackets 32, and has downwardly inclining, apertured ears 33 for the reception of guy wires 34.

The opposite ends of box beam 35 are anchored at .36 on brackets 37, the latter being riveted to the inner faces of brace plates 22.

Face plate 29 carries or may be considered an element of internal gear 38, which, in its preferred form, is of lantern wheel type, that is, the teeth are in the form of bars or rollers (here they are shown as rollers) held between laterally spaced plates, though it lies within the scope of my broader claims to substitute any other suitable type of internal gear. I utilize face plate 29 as one of the gear plates, the other gear plate being in the form of a ring 39 which is of angular cross section, the edge of one of the ring flanges being held in engagement with plate 29- by bolts 40 extending from the other ring flange to the face plate. Bolts 44 are arranged in a circle which is concentrio with aperture 30, and serve to support The rollers are free to revolve upon bolts 44 and function-as the teeth of gear 38. By reason of the described arrangement, individual teeth may be re moved for replacement or repair without disassembly or dismounting the entire gear. Furthermore, ring 39 and plate 29 provide a three sided housing for the rollers and protect them against injury It will be evident that gear 38 may be made up as described very much more cheaply than could a usual internal gear of like size.

Beam 35 and cap 31 support pillow blocks 36 and 37 respectively, and the blocks, in turn hold main crank shaft 46 in coaxial rela tion with gear 38. YVhile shaft 46 may be journaled in the pillow blocks in any suitable way, 1 have, in Fig. 6 shown a preferred arrangement and will described it with some particularity, since there are certain features of novelty disclosed.

Blocks 36 and 37 are substantially of identical construction, each comprising a cylindrical body member 47 having integral base extensions 48 through which anchor bolts 49 extend. The body members each have bores of two diameters 50 and 51, there thus being formed internal, annular shoulders 52, the shoulders of the two blocks being in opposed relation. Ball bearings 53 are positioned within the larger bores 51 and against shoulders 52, sleeve 54 extending between the bearings and forming a housing for shaft 46, the latter having tight fit within the inner ring or race 53 of bearings 53. Sleeve 54 has internal bushings 55 at its opposite ends whereby it may i have proper bearing with the shaft, said shaft preferably being of reduced diameter where it extends between bushings, for obvious reasons. A lock nut 56 is threaded on shaft extension 46 and has side hearing against thrust ring 57 which engages the outer face of race 53 to hold the shaft against longitudinal play.

Ring caps 58 are bolted to the blocks and have oil retention or sealing felts 59 which are adapted to wipe the shaft during rotation thereof. Lubricants may be fed to the interior of the blocks through plate apertures 58 Keyed to shaft extension 46 is a drive sprocket 59 which may be of any suitable design, though I find the illustrated form to be particularly well adapted to the purpose, especially when the sprocket is of relatively large diameter. This sprocket consists of a split plate or spider 60, of octagonal outline and having hub 61 and reinforcing ribs 62, which is clamped and keyed to shaft extension 46 the spider, in turn, carrying a detachable angle iron frame 63 to which sprocket ring 64 is bolted.

Integral with the other end of shaft 46 is main crank 65, which, in its preferred embodiment, is of forked formation, main crank pin 66 extending between and being journaled in the ends of the horizontally spaced fork arms 67. Ball bearings 68 for pin 66 are mounted in arms 67 in the manner clearly illustrated in Fig. 6, this figure also clearly showing how pin hub 69 and retention nut 7 O on the reduced pin end 71 hold the pin from longitudinal displace ment. Cap 72 protects the free end of the pin and prevents leakage of oil from the associated ball bearing. In arms 67 are felt rings 73 which prevent the leakage of oil there-past.

Qn pin 66 is clamped and keyed a split spurgear 74 which is held in constant mesh with gear 38, the ratio of gears 38 and 74 being exactly two to one.

Now it lies within the scope of my invention, considered in its broader aspects, to mount the hereinafter described secondary crank pin (through which connection is made between the jack, proper, and the pump rods) in various manners. It is necessary that the projected longitudinal axis of this pin meet the pitch circle of the spur gear in order that true vertical straight line reciprocation may be imparted to said pin. To bring about this condition, I prefer to provide an independent, secondary crank arm 7 5 which is integral with pin 66 and,

of course, rotates as one with the spur gear.-

The main crank pin 66 thus functions as the crank shaft for secondary crank 7 5. It will be noted, however, I have reduced the double overhang of the cranks to a minimum, it being thus made possible to grip rod It at a point close to the supporting structure, an obvious feature of advantage.

The hub 76 of crank carries secondary crank or wrist pin 77 (F gs. 8 and 9), the center to center distance between pins 66 and 77 being equal to the pitch radius of gear 7 1.

Pin 7 7 is rotatably mounted in hub 76, I thereby be ng enabled to connect the pin rigidly to pump rod R, instead of providing a bearing collar on the pin, as would be necessary were a stationarily mounted pin to be substituted. With the use of such a collar, bearing in mind that the projected longitudinal axis of the pump rod should intersect the projected longitudinal. axis of the pin or its collar, it will be seen that attachment of a pump rod in proper relation thereto would be a matter of some difiiculty. On the other hand, with the use of a pin which may be held against rotation during crank rotation, it is possible to provide a very simple, ef ticient type of rod grip rigidly connectedto or integral with the pin.

My preferred method. of so mounting the pin and its integral rod grip is best illustrated in Figs. 8, 9 and 10. Between pin 77 and hub 76 are provided ball bearings 78, 7 9, it be ng notedthat one end 80 of the pin is threaded and of reduced diameter, while the other end of the pin has an enlarged portion 81 which has a peripheral groove 82 adapted to take felt sealing washer 83, the latter wiping the inner peripheral face of the hub bore for preventing leakage of oil introduced to said bore through way 84-. A tubular spacer 85 surrounds pin 77 between bearings 78 and 79 and the bearing and spacer assembly is held against longitudinal displacement between internal, annular hub shoulders 86, 87 and ring cap 88, respectively. The pin, in turn, is held against longitudinal displacement with respect to the bearings by the engagement of annular face or shoulder 89 of enlargei'nent 81 with hearing 78, and the engagementof thrust collar 90, removably held on the threaded portion 80 by retention nut 91, with the in ner face of bearing 79. Cap 92 is bolted to ring cap 88 and covers the central aperture thereof to prevent the loss of oil from the bore of hub 76.

Grip 93 comprises body member 9+1 integral with pin 77 and having a vertically extending channel. 95 which opens to one side of the body member rather than to the front thereof. There are provided three i-ertically spaced sockets 96 in the body member, which sockets open into and extend transversely beyond channel 95, the body member being ribbed at 97 to allow such extension and the vertical walls'98 connecting these ribs having forwardly opening notches 99 to receive the threaded shanks 100 of clamp eyes 101. The apertures 102 of eyes 101 are of substantially oval outline, as viewed in plan, the minor axes of the ovals being such that rod R may be comfortably taken therein, while relative transverse movement of rod and eye tends to wedge them tightly together. So also, channel 95, considered in transverse cross section, tapers down somewhat sharply from its mouth and is so located and of such proportions that when rod R of given diameter is tightly engaged by the opposite walls of the channel the longitudinal axis of the rod is inthe vertical axial plane of pin 77.

In making connection between therod and grip, the rod is first sprung clear of the grip to allow the clamp eyes to be slidj down over the end of the rod. The rod is then allowed to spring back, it being guided into channel 95, clamps 101 being guidedinto sockets 96, and shanks 100 beingguided'into notches 99. A plate 103, having three holes 101 to take shanks 100, with clearance, is then moved into position against the side faces of ribs 97, and nuts 105 are threaded onto the shanks. By taking up the nuts after they engage plate 104, eyes 101 are drawn forcibly towards the plate, red It consequently being tightly wedged or clamped between the channel walls and the opposite defining walls of apertures 102.

Of course, with the grip once attached to the red, the rod may be shifted vertically with respect to the grip without disassembling the latter, it merely being necessary to loosen nuts 105 and push the eyes back sufiiciently to rel eve the binding engagement between the rod and grip elements.

It will be noted that the transverse axis of channel 95 and the coincidentmajor axes of the eyes, when said eyes are in operative position, incl ne outwardly from the vertical axial. plane of the pin, rather than being. at right angles thereto. By reason of this provision, the rod maybe grippednt a point relatively close to hub 7 0, an obviously desirablecondition, and yet shanks 100 and nuts 105 are brought horizontally well clear of the hub so they may be easily reached for manipulation and adjustment.

Secured to frame work 63 of the drive sprocket is a weight 106 which is arranged to counterbalance the cranks and their associated mechanism.

Assume that power from any suitable source (not indicated) be delivered through sprockets 59 to rotate shaft 16 and hence crank 65 in clockwise direction as viewed in Fig. 2. Gear 74 and crank 7 5 are simultaneously caused to rotate in a counter-clockwise direction since gear 74, keyed to the main crank pin, is maintained in constant mesh with fixed gear 38. The resultant movement of secondary crank pin 76 is of a rectilinear nature, or may be described as straight-line vertical reciprocation. It is believed it is unnecessary to trace the movement of the secondary pin, as the principle of operation is an old one and well known to those skilled in the art.

It is believed a full understanding of the invention will be had from the foregoing, but it is to be understood that the drawings and description are to be considered merely as illustrative of and not restrictive on the broader claims appended hereto, for various changes in design, structure and arrangement may be made without departing from the spirit and scope of said claims.

I claim:

1. A power head for deep well pumps, that includes a supporting member, an internal gear stationarily fixed on the member, a crank shaft journaled on the member, a main crank on the shaft, a crank pin, a spur gear on the pin and held thereby in mesh with the internal gear, means for transmitting rotary motion to the crank shaft, the diameter of the internal gear being twice that of the spur gear, all in a manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, a secondary crank connected with said'spur gear to rotate therewith, a wrist pin for the secondary crank and mounted for rotation with respect thereto, and a rod grip rigidly carried by said wrist pin.

2. A power head for deep well pumps, that includes a supportin member, an internal gear stationarily fixed on the member, a crank shaft journaled on the member, a forked main crank on the shaft, a crank pin extending between and journalcd in the forked arms, a spur gear keyed to the pin between the arms and held thereby in mesh with the internal gear, means for transmitting rotary motion to the crank shaft, the diameter of the internal. gear being twice that of the spur gear, all in a manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, a secondary. crank connected with said spur gear to rotate therewith, a wrist pin on the secondary crank, and a rod grip carried by said wrist pin.

3. In a power head for deep well pumps, a supporting structure, a vertical face plate carried by the structure, a ring of equispaced pins extending ho "izontally from the face plate, a ring member of angular cross section held with one of its flange edges against the face plate and with its other flange overlying the outer extremities of the pins, said pins being arranged to serve as the teeth of an internal gear, a crank shaft journaled on the member, a main crank on the shaft, a crank pin, a spur gear on the pin and held thereby in mesh with the internal gear, means for transmitting rotary motion to the crank shaft, the diameter of the internal gear being twice that of the spur gear, all ma manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, and a rod grip operatively connected to said spur gear in a manner whereby rotation of said gear im parts straight line, vertical. reciprocation to the grip.

l. In a power head for deep well pumps, a supporting structure, a vertical face plate carried by the structure, a ring of equispaced pins extending horizontally from the face plate, a ring member of angular cross section held with one of its flange edges against the face plate and with its other flange overlying the outer extremities of the pins, rollers on the pins between the plate and ring member, said rollers being arranged to serve as the teeth of an internal gear, a crank shaft journaled on the m-em ber, a main crank on the shaft, a crank sin, a spur gear on the pin and held thereby in mesh with the internal gear, means for transmitting rotary motion to the crank shaft, the diameter of the internal gear being twice that of the spur gear, all in a manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, and a rod grip operativ-ely connectedto said spur gear in a manner whereby rotation of said gear imparts straight line, vertical reciprocation to the grip.

5. In a device of the character described, a supporting structure including a tripodal frame, a vertical, gear supporting member extending vertically upwardly from two of the tripod legs, an internal gear on said supporting member, a crank shaft journaled on the supporting structure, a main crank on the shaft, a crank pin, a spur gear on the pin and held thereby in mesh with the in ternal gear, means for transmittin rotary motion to the crank shaft, the diameter of the internal gear being twice that of the spur gear, all in a manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, and rod grip operatively conn cted to said spurgear in a manner whereby rotation of said gear imparts straight line, vertical reci 'n'ocation to the grip.

6. In a device of the character described, a supporting structure including a tripodal frame, a vertical, gear supporting member extending vertically upwardly from two of the tripod legs, an internal gear on said supporting member, a pair of spaced brace plates connecting said supporting member and the tripod legs, a cap on the tripod, a cross beam extending between and supported by said brace plates, a crank shaft journaled on the cap and beam, a main crank on the shaft, a crank pin, a spur gear on the pin and held thereby in mesh with the internal gear, means for transmitting rotary motion to the crank shaft, the diameter of the internal gear being twice that of the spur gear, all in a manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, and a rod grip operatively connected to said spur gear in a manner whereby rotation of said gear imparts straight line, vertical reciprocation to the grip.

7. A rod grip adapted to be carried by the wrist pin of a straight-line power head, including a body member having a vertically extending rod taking channel whose longitudinal axis intersects the projected longitudinal axis of the wrist pin, detachable clamping eyes adapted to take the rod in their apertures and to be moved transversely across the channel, and means for so moving the eyes and thereby wedging the rod between the channel walls and the opposite defining walls of the eye apertures.

8. A rod grip adapted to be carried by the wrist pin of a straight-line power head, including a body member having a vertically extending rod taking channel whose longitudinal axis intersects the projected. longitudinal axis of the wrist pin, the body member being provided with transverse sockets that open into the channel, detachable clamping eyes adapted to take the rod in their apertures and to be supported in and moved longitudinally through said sockets. and means for so moving the eyes and thereby wedging the rod between the channel walls and the opposite defining walls of the eye apertures.

9. A rod grip adapted to be carried by the wrist pin of a straight-line power head, including a body member having a vertically extending rod taking channel whose longitudinal axis intersects the projected longitudinal axis of the wrist pin, the body member being provided with transverse sockets that open into the channel at oile end and open't o the side of the block at the other end, clantiping eyes having threaded shanks, said eyes being adapted to take the rod in their apertures and to be supported in and moved longitudinally through said sockets, the threaded shanks being adapted to extend through and beyond the open ends of the sockets at the sides of the body member, and nuts on the shanks adapted, when threaded over the shanks, to so move the eyes and thereby wedge the rod between the channel walls and the opposite defining walls of the eye apertures.

10. A power head for deep well pumps, that includes a supporting member, an internal gear stationarily fixed on the member, a crank shaft journaled on the member, a main crank on the shaft, a crank pin, a spur gear on the pin and held thereby in mesh with the internal gear, means for transmit ting rotary motion to the crank shaft, the diameter of the internal gear being twice that of the spur gear. all in a manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, a secondary crank on said crank pin, a wrist pin for the secondary crank and mounted for rotation with respect thereto, and a rod grip carried by said wrist pin; said grip having a vertically extending rod taking chan nel opening to one side thereof, and movable clamping members on the grip and adapted to be moved to wedge the rod in said channel, and means for so moving the clamping members; said channel being located so its longitudinal axis intersects the longitudinal axis of the wrist pin.

11. A power head for deep well pumps, that includes a supporting member, an in ternal gear stationarily fixed on the member, a crank shaft jonrnaled on the member, a main crank on the shaft, a crank pin, a spur gear on the pin and held thereby in mesh with the internal gear, means for transmitting rotary motion to the crank shaft, the diameter of the internal gear being twice that of the spur gear. all in a manner whereby one revolution of the crank shaft in a given direction causes the spur gear to rotate one revolution in the opposite direction, a secondary crank on said crank pin, a wrist pin for the secondary crank and mounted for rotation with respect thereto, and a rod grip rigidly carried by said wrist pin, said grip including a body member having a vertically extending rod-taking channel whose longitudinal axis intersects the projected longitudinal axis of the wrist pin, detachable clamping eyes adapted to take the rod in their apertures and to be moved transversely across the channel, and means for so moving the eyes and ,...iereby wedging the ill rod between the channel walls and the opposite defining walls of the eye apertures,

12. In a rod grip adapted to be carried by the wrist pin of a straight-line power head, a body member having a vertically extending rod taking channel whose longitudinal axis intersects the projected longitudinal axis of the wrist pin, a movable clamping member associated with the body member and adapted to be moved towards the body member to hold the rod in said channel, and means for so moving the clamping member.

13. In a rod grip adapted to be carried by the wrist pin of a straight-line power head,

a body member rigidly connected to the wrist pin, and a movable clamping member associated with the body member and adapted to be moved towards said body member to hold said rod rigidly between said body member and clamping member with the longitudinal axis of the rod intersecting the projected longitudinal axis of the wrist pin, and means for so moving the clamping member.

In witness that I claim the foregoing I have hereunto subscribed my name this 30 day of July, 1925. I

EDWARD E. STEVENSON. 

